Semiconductor substrate support with internal channels

ABSTRACT

Exemplary substrate support assemblies may include an electrostatic chuck body defining a substrate support surface. The support assemblies may include a support stem coupled with the electrostatic chuck body. The support assemblies may include an electrode embedded within the electrostatic chuck body proximate the substrate support surface. The support assemblies may include a ground electrode embedded within the electrostatic chuck body. The support assemblies may include one or more channels formed within the electrostatic chuck body between the electrode and the ground electrode.

TECHNICAL FIELD

The present technology relates to components and apparatuses forsemiconductor manufacturing. More specifically, the present technologyrelates to substrate support assemblies and other semiconductorprocessing equipment.

BACKGROUND

Integrated circuits are made possible by processes which produceintricately patterned material layers on substrate surfaces. Producingpatterned material on a substrate requires controlled methods forforming and removing material. Substrate supports may play an importantrole in semiconductor processing, with aspects related to providingtemperature control for a substrate, to embedded electrodes utilized forplasma formation within a processing chamber. Coordinating the manyrelated aspects of a semiconductor substrate support may involvecompeting characteristics and materials. As fabrication outcomes becomemore sensitive to processing conditions, the aspects of a substratesupport may have a significant impact on a number of processingcharacteristics.

Thus, there is a need for improved systems and methods that can be usedto produce high quality devices and structures. These and other needsare addressed by the present technology.

SUMMARY

Exemplary substrate support assemblies may include an electrostaticchuck body defining a substrate support surface. The support assembliesmay include a support stem coupled with the electrostatic chuck body.The support assemblies may include an electrode embedded within theelectrostatic chuck body proximate the substrate support surface. Thesupport assemblies may include a ground electrode embedded within theelectrostatic chuck body. The support assemblies may include one or morechannels formed within the electrostatic chuck body between theelectrode and the ground electrode.

In some embodiments, the electrostatic chuck body may be a monolithicbody of a ceramic material incorporating each of the electrode, theground electrode, and the one or more channels. The assemblies mayinclude a heater embedded within the electrostatic chuck body betweenthe electrode and the ground electrode. The one or more channels mayinclude a plurality of channels. A first channel of the plurality ofchannels may be formed within the electrostatic chuck body between theelectrode and the heater. A second channel of the plurality of channelsmay be formed within the electrostatic chuck body between the groundelectrode and the heater. A third channel of the plurality of channelsmay be formed within the electrostatic chuck body between the electrodeand the heater vertically offset within the electrostatic chuck bodyfrom the first channel of the plurality of channels. The first channelmay include a set of first interconnected channels. The channels mayinclude a plurality of first annular channels distributed across a firstplane of the electrostatic chuck body. The channels may include aplurality of first channel interconnects distributed radially betweeneach first annular channel of the plurality of first annular channels.

The third channel may include a set of second interconnected channels.The channels may include a plurality of second annular channelsdistributed across a second plane of the electrostatic chuck body. Thesecond plane of the electrostatic chuck body may be vertically offsetfrom the first plane of the electrostatic chuck body. The channels mayinclude a plurality of second channel interconnects distributed radiallybetween each second annular channel of the plurality of second annularchannels. The plurality of second annular channels may be radiallyoffset from the plurality of first annular channels. The plurality ofsecond channel interconnects may be azimuthally offset from theplurality of first channel interconnects. The second channel may includea set of third interconnected channels. The channels may include aplurality of third annular channels distributed across a third plane ofthe electrostatic chuck body. The third plane of the electrostatic chuckbody may be vertically offset from the first plane of the electrostaticchuck body and the second plane of the electrostatic chuck body. Thechannels may include a plurality of third channel interconnectsdistributed radially between each third annular channel of the pluralityof third annular channels. Each channel of the plurality of thirdannular channels may be vertically aligned with an associated channel ofthe plurality of first annular channels. The plurality of second channelinterconnects may be azimuthally aligned with the plurality of firstchannel interconnects. The assemblies may include a fourth channelformed within the third plane of the electrostatic chuck body. Thechannel may be configured to seat a thermocouple extended through thesupport stem coupled with the electrostatic chuck body.

Some embodiments of the present technology may encompass substratesupport assemblies. The assemblies may include an electrostatic chuckbody defining a substrate support surface. The assemblies may include asupport stem coupled with the electrostatic chuck body. The assembliesmay include an electrode embedded within the electrostatic chuck bodyproximate the substrate support surface. The assemblies may include aground electrode embedded within the electrostatic chuck body. Theassemblies may include a first set of interconnected channels formedwithin the electrostatic chuck body between the electrode and the groundelectrode. The assemblies may include a second set of interconnectedchannels formed within the electrostatic chuck body between theelectrode and the ground electrode. The second set of interconnectedchannels may be radially offset from the first set of interconnectedchannels. The first set of interconnected channels may be maintained atleast 5 mm from a radial edge of the electrostatic chuck body. The firstset of interconnected channels and the second set of interconnectedchannels may be maintained at atmospheric pressure.

In some embodiments, an effective capacitance within the electrostaticchuck body between the electrode and the ground electrode may be lessthan or about 1,000 pF. The electrostatic chuck body may becharacterized by a volume percentage of air greater than or about 10%.The assemblies may include a heater positioned between the electrode andthe ground electrode. The assemblies may also include a third set ofinterconnected channels formed within the electrostatic chuck bodybetween the heater and the ground electrode.

Some embodiments of the present technology may encompass substratesupport assemblies. The assemblies may include an electrostatic chuckbody defining a substrate support surface. The assemblies may include asupport stem coupled with the electrostatic chuck body. The assembliesmay include an electrode embedded within the electrostatic chuck bodyproximate the substrate support surface. The assemblies may include aground electrode embedded within the electrostatic chuck body. Theassemblies may include a heater embedded within the electrostatic chuckbody between the electrode and the ground electrode. The assemblies mayinclude a first set of interconnected channels formed within theelectrostatic chuck body between the electrode and the heater. Theassemblies may include a second set of interconnected channels formedwithin the electrostatic chuck body between the first set ofinterconnected channels and the heater. The assemblies may include athird set of interconnected channels formed within the electrostaticchuck body between the heater and the ground electrode.

Such technology may provide numerous benefits over conventional systemsand techniques. For example, incorporating channels within a substratesupport may improve the effective capacitance between embeddedelectrodes. Additionally, coordination of the channels may allow reduceddistance between a hot electrode and a ground electrode while limitingeffective capacitance. These and other embodiments, along with many oftheir advantages and features, are described in more detail inconjunction with the below description and attached figures.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the disclosedtechnology may be realized by reference to the remaining portions of thespecification and the drawings.

FIG. 1 shows a schematic cross-sectional view of an exemplary plasmasystem according to some embodiments of the present technology.

FIG. 2 shows a schematic partial cross-sectional view of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology.

FIG. 3 shows a schematic plan view of a portion of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology.

FIG. 4 shows a schematic plan view of a portion of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology.

FIG. 5 shows a schematic plan view of a portion of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology.

FIG. 6 shows a schematic partial cross-sectional view of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology.

FIG. 7 shows a schematic plan view of a portion of an exemplaryelectrostatic chuck body according to some embodiments of the presenttechnology.

Several of the figures are included as schematics. It is to beunderstood that the figures are for illustrative purposes, and are notto be considered of scale unless specifically stated to be of scale.Additionally, as schematics, the figures are provided to aidcomprehension and may not include all aspects or information compared torealistic representations, and may include exaggerated material forillustrative purposes.

In the appended figures, similar components and/or features may have thesame reference label. Further, various components of the same type maybe distinguished by following the reference label by a letter thatdistinguishes among the similar components. If only the first referencelabel is used in the specification, the description is applicable to anyone of the similar components having the same first reference labelirrespective of the letter.

DETAILED DESCRIPTION

Plasma enhanced deposition processes may energize one or moreconstituent precursors to facilitate film formation on a substrate. Anelectrostatic chuck may be used to produce a clamping action against thesubstrate to maintain planarity across the substrate and contact betweenthe substrate and the substrate support. The substrate support mayperform multiple functions during plasma processing. For example, inaddition to chucking the wafer against the substrate support, thesubstrate support may include one or more embedded heaters forcontrolling a temperature of the substrate during processing.Additionally, the substrate support may operate as one of the electrodesfor a capacitively-coupled plasma produced within a substrate processingregion of the semiconductor processing chamber.

An electrode within the substrate support, as well as an opposingfaceplate or showerhead, may operate as two opposingcapacitively-coupled electrodes during plasma processing. This mayproduce a plasma between the components, which may ionize deliveredprecursors and produce reactants that may deposit materials on thesubstrate. While the chamber body may be grounded and operate as aground path in some embodiments, this ground path may cause challengesduring processing. The ground path from a hot electrode within thepedestal to the chamber walls may not be symmetric with gap regionsaround the substrate support and below the substrate support, andelectrical fields may create areas of higher distribution, which mayignite stray plasma in regions around the substrate support. To improveissues with asymmetrical grounding, many substrate supports willadditionally include a ground electrode within the substrate supportitself. The ground electrode within the substrate support may beseparated from the plasma-generating electrode within the platen portionof the substrate support, or the electrostatic chuck body. As manysubstrate supports are a ceramic or dielectric material, shortingbetween these electrodes may not occur, although electrical losses maybe generated through the dielectric body from the hot electrode to theground electrode.

While improving the symmetry of the ground path and incorporating aground electrode within the electrostatic chuck body may reduce strayplasma issues, many conventional technologies must accept the electricallosses from the incorporation of a ground electrode within the substratesupport. One solution to reduce these losses may include increasing athickness of the dielectric material, and thus a corresponding distancebetween the hot electrode and ground electrode, which may reduce thecapacitive losses between these two components. However, due to spaceconstraints within the processing chamber, many substrate supports areconstrained vertically, which may limit the ability to sufficientlyincrease the chuck body thickness. The present technology may overcomethese issues by manipulating the electrical properties of the ceramic ofthe ground plate. By including an amount of air or fluid space withinthe substrate support, an effective capacitance between the hot andground electrodes may be reduced, while maintaining a specifiedthickness of the substrate support.

Although the remaining disclosure will routinely identify specificdeposition processes and chambers utilizing the disclosed technology, itwill be readily understood that the systems and methods are equallyapplicable to other deposition, etch, and cleaning chambers, as well asprocesses as may occur in the described chambers. Accordingly, thetechnology should not be considered to be so limited as for use withthese specific deposition processes or chambers alone. The disclosurewill discuss one possible chamber that may include substrate supportassemblies according to embodiments of the present technology beforeadditional variations and adjustments to this system according toembodiments of the present technology are described.

FIG. 1 shows a cross-sectional view of an exemplary processing chamber100 according to some embodiments of the present technology. The figuremay illustrate an overview of a system incorporating one or more aspectsof the present technology, and/or which may be specifically configuredto perform one or more operations according to embodiments of thepresent technology. Additional details of chamber 100 or methodsperformed may be described further below. Chamber 100 may be utilized toform film layers according to some embodiments of the presenttechnology, although it is to be understood that the methods maysimilarly be performed in any chamber within which film formation mayoccur. The processing chamber 100 may include a chamber body 102, asubstrate support 104 disposed inside the chamber body 102, and a lidassembly 106 coupled with the chamber body 102 and enclosing thesubstrate support 104 in a processing volume 120. A substrate 103 may beprovided to the processing volume 120 through an opening 126, which maybe conventionally sealed for processing using a slit valve or door. Thesubstrate 103 may be seated on a surface 105 of the substrate supportduring processing. The substrate support 104 may be rotatable, asindicated by the arrow 145, along an axis 147, where a shaft 144 of thesubstrate support 104 may be located. Alternatively, the substratesupport 104 may be lifted up to rotate as necessary during a depositionprocess.

A plasma profile modulator 111 may be disposed in the processing chamber100 to control plasma distribution across the substrate 103 disposed onthe substrate support 104. The plasma profile modulator 111 may includea first electrode 108 that may be disposed adjacent to the chamber body102, and may separate the chamber body 102 from other components of thelid assembly 106. The first electrode 108 may be part of the lidassembly 106, or may be a separate sidewall electrode. The firstelectrode 108 may be an annular or ring-like member, and may be a ringelectrode. The first electrode 108 may be a continuous loop around acircumference of the processing chamber 100 surrounding the processingvolume 120, or may be discontinuous at selected locations if desired.The first electrode 108 may also be a perforated electrode, such as aperforated ring or a mesh electrode, or may be a plate electrode, suchas, for example, a secondary gas distributor.

One or more isolators 110 a, 110 b, which may be a dielectric materialsuch as a ceramic or metal oxide, for example aluminum oxide and/oraluminum nitride, may contact the first electrode 108 and separate thefirst electrode 108 electrically and thermally from a gas distributor112 and from the chamber body 102. The gas distributor 112 may defineapertures 118 for distributing process precursors into the processingvolume 120. The gas distributor 112 may be coupled with a first sourceof electric power 142, such as an RF generator, RF power source, DCpower source, pulsed DC power source, pulsed RF power source, or anyother power source that may be coupled with the processing chamber. Insome embodiments, the first source of electric power 142 may be an RFpower source.

The gas distributor 112 may be a conductive gas distributor or anon-conductive gas distributor. The gas distributor 112 may also beformed of conductive and non-conductive components. For example, a bodyof the gas distributor 112 may be conductive while a face plate of thegas distributor 112 may be non-conductive. The gas distributor 112 maybe powered, such as by the first source of electric power 142 as shownin FIG. 1, or the gas distributor 112 may be coupled with ground in someembodiments.

The first electrode 108 may be coupled with a first tuning circuit 128that may control a ground pathway of the processing chamber 100. Thefirst tuning circuit 128 may include a first electronic sensor 130 and afirst electronic controller 134. The first electronic controller 134 maybe or include a variable capacitor or other circuit elements. The firsttuning circuit 128 may be or include one or more inductors 132. Thefirst tuning circuit 128 may be any circuit that enables variable orcontrollable impedance under the plasma conditions present in theprocessing volume 120 during processing. In some embodiments asillustrated, the first tuning circuit 128 may include a first circuitleg and a second circuit leg coupled in parallel between ground and thefirst electronic sensor 130. The first circuit leg may include a firstinductor 132A. The second circuit leg may include a second inductor 132Bcoupled in series with the first electronic controller 134. The secondinductor 132B may be disposed between the first electronic controller134 and a node connecting both the first and second circuit legs to thefirst electronic sensor 130. The first electronic sensor 130 may be avoltage or current sensor and may be coupled with the first electroniccontroller 134, which may afford a degree of closed-loop control ofplasma conditions inside the processing volume 120.

A second electrode 122 may be coupled with the substrate support 104.The second electrode 122 may be embedded within the substrate support104 or coupled with a surface of the substrate support 104. The secondelectrode 122 may be a plate, a perforated plate, a mesh, a wire screen,or any other distributed arrangement of conductive elements. The secondelectrode 122 may be a tuning electrode, and may be coupled with asecond tuning circuit 136 by a conduit 146, for example a cable having aselected resistance, such as 50 ohms, for example, disposed in the shaft144 of the substrate support 104. The second tuning circuit 136 may havea second electronic sensor 138 and a second electronic controller 140,which may be a second variable capacitor. The second electronic sensor138 may be a voltage or current sensor, and may be coupled with thesecond electronic controller 140 to provide further control over plasmaconditions in the processing volume 120.

A third electrode 124, which may be a bias electrode and/or anelectrostatic chucking electrode, may be coupled with the substratesupport 104. The third electrode may be coupled with a second source ofelectric power 150 through a filter 148, which may be an impedancematching circuit. The second source of electric power 150 may be DCpower, pulsed DC power, RF bias power, a pulsed RF source or bias power,or a combination of these or other power sources. In some embodiments,the second source of electric power 150 may be an RF bias power.

The lid assembly 106 and substrate support 104 of FIG. 1 may be usedwith any processing chamber for plasma or thermal processing. Inoperation, the processing chamber 100 may afford real-time control ofplasma conditions in the processing volume 120. The substrate 103 may bedisposed on the substrate support 104, and process gases may be flowedthrough the lid assembly 106 using an inlet 114 according to any desiredflow plan. Gases may exit the processing chamber 100 through an outlet152. Electric power may be coupled with the gas distributor 112 toestablish a plasma in the processing volume 120. The substrate may besubjected to an electrical bias using the third electrode 124 in someembodiments.

Upon energizing a plasma in the processing volume 120, a potentialdifference may be established between the plasma and the first electrode108. A potential difference may also be established between the plasmaand the second electrode 122. The electronic controllers 134, 140 maythen be used to adjust the flow properties of the ground pathsrepresented by the two tuning circuits 128 and 136. A set point may bedelivered to the first tuning circuit 128 and the second tuning circuit136 to provide independent control of deposition rate and of plasmadensity uniformity from center to edge. In embodiments where theelectronic controllers may both be variable capacitors, the electronicsensors may adjust the variable capacitors to maximize deposition rateand minimize thickness non-uniformity independently.

Each of the tuning circuits 128, 136 may have a variable impedance thatmay be adjusted using the respective electronic controllers 134, 140.Where the electronic controllers 134, 140 are variable capacitors, thecapacitance range of each of the variable capacitors, and theinductances of the first inductor 132A and the second inductor 132B, maybe chosen to provide an impedance range. This range may depend on thefrequency and voltage characteristics of the plasma, which may have aminimum in the capacitance range of each variable capacitor. Hence, whenthe capacitance of the first electronic controller 134 is at a minimumor maximum, impedance of the first tuning circuit 128 may be high,resulting in a plasma shape that has a minimum aerial or lateralcoverage over the substrate support. When the capacitance of the firstelectronic controller 134 approaches a value that minimizes theimpedance of the first tuning circuit 128, the aerial coverage of theplasma may grow to a maximum, effectively covering the entire workingarea of the substrate support 104. As the capacitance of the firstelectronic controller 134 deviates from the minimum impedance setting,the plasma shape may shrink from the chamber walls and aerial coverageof the substrate support may decline. The second electronic controller140 may have a similar effect, increasing and decreasing aerial coverageof the plasma over the substrate support as the capacitance of thesecond electronic controller 140 may be changed.

The electronic sensors 130, 138 may be used to tune the respectivecircuits 128, 136 in a closed loop. A set point for current or voltage,depending on the type of sensor used, may be installed in each sensor,and the sensor may be provided with control software that determines anadjustment to each respective electronic controller 134, 140 to minimizedeviation from the set point. Consequently, a plasma shape may beselected and dynamically controlled during processing. It is to beunderstood that, while the foregoing discussion is based on electroniccontrollers 134, 140, which may be variable capacitors, any electroniccomponent with adjustable characteristic may be used to provide tuningcircuits 128 and 136 with adjustable impedance.

FIG. 2 shows a schematic partial cross-sectional view of an exemplarysubstrate support 200 according to some embodiments of the presenttechnology. For example, substrate support 200 may illustrate a portionof substrate support 104 described above, which may include any aspectof that support assembly, and may illustrate additional details of thatsupport assembly. Substrate support 200 may illustrate a simplifiedcross-section of a support structure, which may include a number ofother components or aspects as previously described, or as may beincluded in substrate supports. It is to be understood that substratesupport 200 is not illustrated to any particular scale, and is includedmerely to illustrate aspects of the present technology. Substratesupport 200 may be included within a chamber as previously described, aswell as any other processing chamber, which may define a substrateprocessing region, such as with one or more walls of a chamber body, orother components positioned within the processing chamber. Substratesupport 200 may show a partial view of components and couplings withinan exemplary semiconductor processing system, and may not include all ofthe components, such as the chamber components and characteristicspreviously described, which are understood to be incorporated in someembodiments about and with substrate support 200.

Substrate support 200 may include a number of components bonded, welded,joined, sintered, formed, or otherwise coupled with one another. Thesubstrate support assembly may include an electrostatic chuck body 205,which may include one or more components embedded or disposed within thebody. The components incorporated within the top puck may not be exposedto processing materials in some embodiments, and may be fully retainedwithin the chuck body 205. Electrostatic chuck body 205 may define asubstrate support surface 207, and may be characterized by a thicknessand length or diameter depending on the specific geometry of the chuckbody. In some embodiments the chuck body may be elliptical, and may becharacterized by one or more radial dimensions from a central axisthrough the chuck body. It is to be understood that the top puck may beany geometry, and when radial dimensions are discussed, they may defineany length from a central position of the chuck body.

Electrostatic chuck body 205 may be coupled with a stem 210, which maysupport the chuck body and may include channels for delivering andreceiving electrical and/or fluid lines that may couple with internalcomponents of the chuck body 205. Chuck body 205 may include associatedchannels or components to operate as an electrostatic chuck, although insome embodiments the assembly may operate as or include components for avacuum chuck, or any other type of chucking system. Stem 210 may becoupled with the chuck body on a second surface of the chuck bodyopposite the substrate support surface. The electrostatic chuck body 205may include an electrode 215 embedded within the chuck body proximatethe substrate support surface. Electrode 215 may be electrically coupledwith a power source for operating as a plasma-generating electrode aloneor with another component, such as with a faceplate or other chambercomponent for producing a capacitively-coupled plasma above the wafer.The power source may be configured to provide energy or voltage to theelectrically conductive chuck electrode 215, which may also operate as achucking electrode in some embodiments.

In some embodiments the electrostatic chuck body 205 and/or the stem 210may be insulative or dielectric materials. For example, oxides,nitrides, carbides, and other materials may be used to form thecomponents, as well as a range of polymeric materials, includingpolystyrene or other materials, including cross-linked materials.Exemplary materials may include ceramics, including aluminum oxide,aluminum nitride, silicon carbide, tungsten carbide, and any other metalor transition metal oxide, nitride, carbide, boride, or titanate, aswell as combinations of these materials and other insulative ordielectric materials. Different grades of ceramic materials may be usedto provide composites configured to operate at particular temperatureranges, and thus different ceramic grades of similar materials may beused for the top puck and stem in some embodiments. Dopants may beincorporated in some embodiments to adjust electrical properties orother characteristics of the components. Exemplary dopant materials mayinclude yttrium, magnesium, silicon, iron, calcium, chromium, sodium,nickel, copper, zinc, or any number of other elements known to beincorporated within a ceramic or dielectric material.

The chuck body may include a ground electrode 220, which may be disposedproximate the backside of the chuck body, such as proximate the surfacewith which the stem is coupled. Additionally, a heater 225 may beincorporated within the chuck body, such as between the electrode 215and the ground electrode 220. Electrical couplings for the heater andelectrode may extend through the stem and substrate support toelectrically couple the components with power supplies.

In some embodiments, the electrostatic chuck body may also include ordefine one or more channels within the electrostatic chuck body betweenthe electrode 215 and the ground electrode 220. As explained previously,electrical losses may occur from the electrode 215 to the groundelectrode 220 through the electrostatic chuck body 205. In someembodiments a thickness of the chuck body may be fixed, and thusreducing the electrical losses by increasing a distance between theelectrodes may not be feasible. Accordingly, in some embodiments theelectrical properties of the chuck body may be modified by incorporatinggaps, which may include air or some other fluid or gas pumped into thechannels.

In addition to increasing the chuck body thickness to further separatethe electrodes, increasing air pockets or porosity may reduce theeffective capacitance between the two electrodes within the chuck body.To effectively reduce the capacitance, however, a sufficient volume ofair or fluid may be included. By increasing porosity throughout thesubstrate support, however, leakage may occur. For example, thesubstrate support may be included within a processing chamber that maybe operated under vacuum during semiconductor processing. Channelsformed within the stem and top puck for delivering fluids or electricalconnections may be maintained at atmospheric conditions. When the chuckbody is sufficiently porous, the pressure differential between theatmospheric components and the vacuum conditions within the chamber maycause air to leak through the porous body into the processing chamber.Consequently, simply increasing the porosity of the puck body may notallow a sufficient volume of air to be incorporated to effectivelyreduce capacitance without compromising the operation of the substratesupport with respect to processing.

Accordingly, the present technology may include a number of channelsformed within the electrostatic chuck body to increase a volumepercentage of air or other fluid within the puck between the twoelectrodes, which may reduce the effective capacitance between theelectrodes. The channels may be distributed to limit structural impacton the substrate support. For example, because the electrostatic chuckbody may be formed by a high temperature and pressure sintering process,and then operated under potentially high vacuum conditions, forming asingle volume within the electrostatic chuck body may cause thestructure to collapse during formation or operation. Additionally, heattransfer through the electrostatic chuck body may be greatly impededwith such a volume, which may affect uniformity of heating of asubstrate. Consequently, some embodiments of the present technology mayinclude one or more channels within the substrate support distributed tolimit mechanical and thermal impact on operation of the substratesupport, while improving electrical characteristics of the substratesupport.

As illustrated, the electrostatic chuck body may be a monolithic body ofa ceramic material incorporating each of the hot electrode, the groundelectrode, the heater, and the channels. As will be described furtherbelow, the monolith may be formed by sintering or otherwise joining anumber of plates, such as green bodies, which may define the one or morechannels that in some embodiments may be a plurality of channels. Eachchannel included may be accessible through the stem, which may allowfluid access, and which may prevent the channels from being sealedvolumes within the electrostatic chuck body, for example. A firstchannel 230 may be formed within the electrostatic chuck body 205between the electrode 215 and the heater 225. A second channel 235 maybe formed within the electrostatic chuck body between the electrode 215and the heater 225, and may be formed within the chuck body between thefirst channel 230 and the heater 225. The second channel may bevertically offset within the electrostatic chuck body from the firstchannel as illustrated.

In some embodiments a third channel 240 may be formed within theelectrostatic chuck body between the heater 225 and the ground electrode220. As will be explained further below, each channel may include or becomprised of a set of interconnected channels, which may all be fluidlycoupled to produce a single distributed channel. In embodiments some orall of the channels may be included in substrate support assemblies,although not all channels may be included. For example, in someembodiments only one of the channels may be included, or any two of thechannels may be included. In one non-limiting embodiment only the firstand third channel may be included, in which case the third channel mayconstitute a second channel, for example. Any number of inclusions orexclusions is similarly encompassed by embodiments of the presenttechnology.

Each of the channels included may be distributed along a respectiveplane through the electrostatic chuck body. For example, the firstchannel may extend along a first plane through the electrostatic chuckbody, the second channel may extend along a second plane through theelectrostatic chuck body, and the third channel may extend along a thirdplane through the electrostatic chuck body. Channels may be distributedalong the plane to maintain structural support and sufficient heattransfer through the layers of the substrate support. For example, whenboth first channel 230 and second channel 235 are included, the channelsmay be offset from one another. As illustrated, in some embodimentssecond channel 235 may be offset from associated portions of the firstchannel 230.

Third channel 240 is illustrated as being aligned with first channel230, although in other embodiments third channel 240 may be aligned withsecond channel 235, or may be offset from both first channel 230 andsecond channel 235. In line with third channel 240 may be an additionalaccess 245, which may provide a space for a thermocouple or additionalsensor. Additionally, to limit leakage from any of the channels into thechamber environment, which may be a vacuum environment, in someembodiments a radial outermost portion of any channel may be maintainedat least about 1 mm from an exterior edge of the substrate support, andmay be maintained greater than or about 2 mm from the exterior edge,greater than or about 3 mm, greater than or about 4 mm, greater than orabout 5 mm, greater than or about 6 mm, greater than or about 7 mm,greater than or about 8 mm, greater than or about 9 mm, greater than orabout 10 mm, or more.

As noted previously, electrostatic chuck body 205 may be formed byjoining a number of plates that may define the one or more channels.Channels may be formed within molds or green bodies, which may then besintered together to form a monolithic electrostatic chuck body, whichmay include the channels and components noted previously. FIG. 3 shows aschematic plan view of a portion of an exemplary substrate supportassembly according to some embodiments of the present technology. Thefigure may show a plan view of a first plate 300, which may be a portionof electrostatic chuck body 205 described above. The plate may includeany of the features or characteristics of the chuck body, and may definea first channel 230 within a surface of the plate.

First channel 230 may be a set of interconnected channels formed alongthe surface of the plate 300. The set of interconnected channels may befluidly connected throughout the channel, and may form a singlecontinuous pocket within the surface. First channel 230 may include aportion 305 extending to a central access, which may fluidly couple thefirst channel 230 with the stem 210 of the substrate support, which mayallow the first channel to be maintained at atmospheric conditions, ormay provide access for a fluid to be pumped or flowed into the channelor from the channel in some embodiments. The interconnected channels offirst channel 230 may include a plurality of annular channels 310, orsemi-annular channels, formed within the plate. The annular channels 310may be concentric extending radially outward along the plate. Aplurality of channel interconnects 315 may be formed between the annularchannels 310, which may fluidly couple the annular channels, and providefluid communication throughout first channel 230. First channel 230 mayextend about one or more apertures 320 formed through the plate, whichmay provide access for lift pins to extend through the substratesupport. Because the lift pins may extend into the vacuum conditions ofthe chamber, first channel 230, as well as the other channels throughthe other plates, may not extend through or intersect the apertures tolimit any access between the channels and the processing environment.

FIG. 4 shows a schematic plan view of a portion of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology. The figure may show a plan view of a second plate 400, whichmay be a portion of electrostatic chuck body 205 described above. Theplate may include any of the features or characteristics of the chuckbody, and may define a second channel 235 within a surface of the plate.Plate 400 may include any of the features of first plate 300 describedabove.

For example, second channel 235 may be a set of interconnected channelsformed along the surface of the plate 300, similarly to first channel230. The set of interconnected channels may be fluidly connectedthroughout the channel, and may form a single continuous pocket withinthe surface. Second channel 235 may include a portion 405 extending to acentral access, which may fluidly couple the second channel 235 with thestem 210 of the substrate support, which may allow the second channel tobe maintained at atmospheric conditions, or may provide access for afluid to be pumped or flowed into the channel or from the channel insome embodiments. The interconnected channels of second channel 235 mayinclude a plurality of annular channels 410, or semi-annular channels,formed within the plate. The annular channels 410 may be concentricextending radially outward along the plate. A plurality of channelinterconnects 415 may be formed between the annular channels 410, whichmay fluidly couple the annular channels, and provide fluid communicationthroughout second channel 235.

As illustrated, the annular channels 410 of second plate 400 may beradially offset along a radius of the electrostatic chuck body from theannular channels 310 of first plate 300. This may facilitate bothstructural support across the substrate support when the plates arejoined together, as well as provide improved thermal communicationacross the plates, which may maintain uniform heating through the platesto limit temperature effects that may otherwise be caused by the formedchannels. Additionally, the plurality of second channel interconnects415 may be azimuthally offset about the second plate from the locationabout the first plate where the first channel interconnects 315 may belocated. This may similarly maintain structural support across athickness of the substrate support between planes of the chuck body inwhich channels are formed.

FIG. 5 shows a schematic plan view of a portion of an exemplarysubstrate support assembly according to some embodiments of the presenttechnology. The figure may show a plan view of a third plate 500, whichmay be a portion of electrostatic chuck body 205 described above. Theplate may include any of the features or characteristics of the chuckbody, and may define a third channel 240 within a surface of the plate.Plate 500 may include any of the features of first plate 300 or secondplate 400 described above.

For example, third channel 240 may be a set of interconnected channelsformed along the surface of the plate 500, similarly to first channel230. The set of interconnected channels may be fluidly connectedthroughout the channel, and may form a single continuous pocket withinthe surface. Third channel 240 may include a portion 505 extending to acentral access, which may fluidly couple the third channel 240 with thestem 210 of the substrate support, which may allow the third channel tobe maintained at atmospheric conditions, or may provide access for afluid to be pumped or flowed into the channel or from the channel insome embodiments. In some embodiments, each of the portions 305, 405,and 505 may fluidly couple with an aperture extending at least partwaythrough the substrate support, although the aperture may not fullyextend through a substrate support surface of the substrate support, tolimit any interaction with a processing environment, such as vacuumconditions. The interconnected channels of third channel 240 may includea plurality of annular channels 510, or semi-annular channels, formedwithin the plate. The annular channels 510 may be concentric extendingradially outward along the plate. A plurality of channel interconnects515 may be formed between the annular channels 510, which may fluidlycouple the annular channels, and provide fluid communication throughoutthird channel 240.

As illustrated, the annular channels 510 of third plate 500 may beradially aligned along a radius of the electrostatic chuck body with theannular channels 310 of first plate 300. Additionally, the plurality ofsecond channel interconnects 515 may be azimuthally aligned about thesecond plate with the location about the first plate where the firstchannel interconnects 315 may be located. Although some embodiments asillustrated may include this interconnect arrangement, because thirdchannel 240 may be further removed from first channel 230 and secondchannel 235, in some embodiments third channel 240 may be formed in avariety of arrangements. For example, in some embodiments third channel240 may be formed with one or more of the annular channels 510 or thechannel interconnects 515 being aligned with associated aspects of thesecond channel 235.

Additionally, in some embodiments third channel 240 may be formed withone or more of the annular channels 510 or the channel interconnects 515being offset from associated aspects of the second channel 235 and thefirst channel 230, such that the interconnects of each channel areazimuthally offset from the interconnects of any other channel, and/orthat each of the annular channels 510 may be radially offset from theannular channels of any other channel. Third plate 500 may also definean additional access 245, within which a thermocouple may be seatedduring operation. Access 245 may be a fourth channel or recess formedwithin the third plate 500, and may extend from a central aperture ofthe third plate radially outward along the plate. As illustrated access245 may not intersect any portion of third channel 240 in someembodiments.

Any of the plates may be characterized by a thickness of the plate aswell as a depth of the channel formed within the plate. Although theplates may be of any particular size, in some embodiments, the channelsmay extend at least 25% of the thickness through the plate, and mayextend a depth into the plate of greater than or about 30%, greater thanor about 35%, greater than or about 40%, greater than or about 45%,greater than or about 50%, greater than or about 55%, greater than orabout 60%, greater than or about 65%, greater than or about 70%, greaterthan or about 75%, greater than or about 80%, or more, although in someembodiments the channels may not extend fully through the plate.

Turning to FIG. 6 is shown a schematic partial cross-sectional view ofan exemplary substrate support 600 according to some embodiments of thepresent technology, and which may illustrate the channels. Substratesupport 600 may include any feature, characteristic, or aspect of anycomponent previously described, and may illustrate further detail ofsubstrate support 200 described above. For example, substrate support600 may include an electrode, a heater, and a ground electrode asdiscussed with respect to substrate support 200, and may illustratechannels formed through the chuck body as previously described.

As illustrated, substrate support 600 may show a portion of anelectrostatic chuck body 605 in which a number of channels are defined.The substrate support may include a first channel 230, a second channel235, and a third channel 240, as well as any of the variations discussedpreviously and similarly encompassed by the present technology. As notedabove, when plates are sintered, bonded, or otherwise joined to producethe chuck body 605, the channels may be aligned to maintain structuralsupport throughout the chuck body, as well as to maintain adequate heattransfer through the support. For example, each annular channel ofsecond channel 235 may be radially offset from the annular channels offirst channel 230. This particular cross-sectional view may extend alongchannel interconnects of first channel 230, which may illustrate thatchannel interconnects of second channel 235 are azimuthally offset fromthe channel interconnects of first channel 230. Third channel 240 isshown with alignment to the first channel 230 both radially for theannular channels and azimuthally for the channel interconnects fluidlycoupling the annular channels.

When the plates are joined, which may include additional plates oneither or both sides of the plates defining the channels to produce thecomplete electrostatic chuck body, a thickness of the chuck body may bedefined. Although chuck bodies may be characterized by any thickness inembodiments of the present technology, in some embodiments theelectrostatic chuck body may maintain a distance between a hot electrodeand a ground electrode of less than or about 30 mm, and may maintain adistance between the electrodes of less than or about 25 mm, less thanor about 20 mm, less than or about 18 mm, less than or about 16 mm, lessthan or about 14 mm, less than or about 12 mm, less than or about 10 mm,or less. As the distance between the electrodes decreases, the effectivecapacitance between them may increase, causing losses within the system.

However, by incorporating channels which may produce fluid or air volumewithin the chuck body, the effective capacitance may be reduced. Hence,with electrode spacing within any of the noted ranges, an effectivecapacitance through the chuck body may be less than or about 1,000 pF,and may be less than or about 980 pF, less than or about 960 pF, lessthan or about 950 pF, less than or about 940 pF, less than or about 930pF, less than or about 920 pF, less than or about 910 pF, less than orabout 900 pF, less than or about 890 pF, less than or about 880 pF, lessthan or about 870 pF, less than or about 860 pF, less than or about 850pF, less than or about 840 pF, less than or about 830 pF, less than orabout 820 pF, less than or about 810 pF, less than or about 800 pF, lessthan or about 790 pF, or less. This may occur by increasing the volumepercentage of air within the chuck body by incorporating channels aspreviously described. For example, in some embodiments, the volumepercentage of air within the electrostatic chuck body may be greaterthan or about 2%, and may be greater than or about 4%, greater than orabout 6%, greater than or about 8%, greater than or about 10%, greaterthan or about 12%, greater than or about 14%, greater than or about 16%,greater than or about 18%, greater than or about 20%, or more. Aspreviously described, this volume percentage may not be the result ofincreased porosity, which at these ranges may produce air leaks throughthe chuck body. Consequently, electrostatic chuck bodies according toembodiments of the present technology may be characterized by aneffective capacitance similar to a chuck body with electrode spacingthat may be up to twice the distance or more.

FIG. 7 shows a schematic plan view of a portion of an exemplaryelectrostatic chuck body 700 according to some embodiments of thepresent technology. The chuck body may be included with any system andmay be substituted with chuck body 205, or any other component.Electrostatic chuck body 700 may include a set of channels 705 within asingle layer through the chuck body to produce a percentage air volumeas discussed above. The channels 705 may be fluidly accessible from acentral aperture as previously described, and may be formed between aheater and hot electrode as discussed above. The channels 705 may beformed recessed from an exterior edge of the substrate support tomaintain fluid isolation with a processing region of a chamber in whichthe substrate support may be disposed. A top portion of a substratesupport, such as including a hot electrode and a substrate supportsurface may be joined, bonded, or sintered to the chuck body 700, and astem may be coupled with a backside surface, to produce a substratesupport assembly, which may include any of the components, features, orcharacteristics described above. By utilizing chuck bodies according toembodiments of the present technology, improved electrical performancemay be afforded while maintaining dimensional characteristics ofsubstrate supports.

In the preceding description, for the purposes of explanation, numerousdetails have been set forth in order to provide an understanding ofvarious embodiments of the present technology. It will be apparent toone skilled in the art, however, that certain embodiments may bepracticed without some of these details, or with additional details.

Having disclosed several embodiments, it will be recognized by those ofskill in the art that various modifications, alternative constructions,and equivalents may be used without departing from the spirit of theembodiments. Additionally, a number of well-known processes and elementshave not been described in order to avoid unnecessarily obscuring thepresent technology. Accordingly, the above description should not betaken as limiting the scope of the technology.

Where a range of values is provided, it is understood that eachintervening value, to the smallest fraction of the unit of the lowerlimit, unless the context clearly dictates otherwise, between the upperand lower limits of that range is also specifically disclosed. Anynarrower range between any stated values or unstated intervening valuesin a stated range and any other stated or intervening value in thatstated range is encompassed. The upper and lower limits of those smallerranges may independently be included or excluded in the range, and eachrange where either, neither, or both limits are included in the smallerranges is also encompassed within the technology, subject to anyspecifically excluded limit in the stated range. Where the stated rangeincludes one or both of the limits, ranges excluding either or both ofthose included limits are also included.

As used herein and in the appended claims, the singular forms “a”, “an”,and “the” include plural references unless the context clearly dictatesotherwise. Thus, for example, reference to “a heater” includes aplurality of such heaters, and reference to “the protrusion” includesreference to one or more protrusions and equivalents thereof known tothose skilled in the art, and so forth.

Also, the words “comprise(s)”, “comprising”, “contain(s)”, “containing”,“include(s)”, and “including”, when used in this specification and inthe following claims, are intended to specify the presence of statedfeatures, integers, components, or operations, but they do not precludethe presence or addition of one or more other features, integers,components, operations, acts, or groups.

1. A substrate support assembly comprising: an electrostatic chuck bodydefining a substrate support surface; a support stem coupled with theelectrostatic chuck body; an electrode embedded within the electrostaticchuck body proximate the substrate support surface; a ground electrodeembedded within the electrostatic chuck body; and one or more channelsformed within the electrostatic chuck body between the electrode and theground electrode.
 2. The substrate support assembly of claim 1, whereinthe electrostatic chuck body comprises a monolithic body of a ceramicmaterial incorporating each of the electrode, the ground electrode, andthe one or more channels.
 3. The substrate support assembly of claim 2,further comprising: a heater embedded within the electrostatic chuckbody between the electrode and the ground electrode.
 4. The substratesupport assembly of claim 3, wherein the one or more channels comprisesa plurality of channels, wherein a first channel of the plurality ofchannels is formed within the electrostatic chuck body between theelectrode and the heater.
 5. The substrate support assembly of claim 4,wherein a second channel of the plurality of channels is formed withinthe electrostatic chuck body between the ground electrode and theheater.
 6. The substrate support assembly of claim 5, wherein a thirdchannel of the plurality of channels is formed within the electrostaticchuck body between the electrode and the heater vertically offset withinthe electrostatic chuck body from the first channel of the plurality ofchannels.
 7. The substrate support assembly of claim 6, wherein thefirst channel comprises a set of first interconnected channelscomprising: a plurality of first annular channels distributed across afirst plane of the electrostatic chuck body, and a plurality of firstchannel interconnects distributed radially between each first annularchannel of the plurality of first annular channels.
 8. The substratesupport assembly of claim 7, wherein the third channel comprises a setof second interconnected channels comprising: a plurality of secondannular channels distributed across a second plane of the electrostaticchuck body, wherein the second plane of the electrostatic chuck body isvertically offset from the first plane of the electrostatic chuck body,and a plurality of second channel interconnects distributed radiallybetween each second annular channel of the plurality of second annularchannels.
 9. The substrate support assembly of claim 8, wherein theplurality of second annular channels are radially offset from theplurality of first annular channels, and wherein the plurality of secondchannel interconnects are azimuthally offset from the plurality of firstchannel interconnects.
 10. The substrate support assembly of claim 8,the second channel comprises a set of third interconnected channelscomprising: a plurality of third annular channels distributed across athird plane of the electrostatic chuck body, wherein the third plane ofthe electrostatic chuck body is vertically offset from the first planeof the electrostatic chuck body and the second plane of theelectrostatic chuck body, and a plurality of third channel interconnectsdistributed radially between each third annular channel of the pluralityof third annular channels.
 11. The substrate support assembly of claim10, wherein each channel of the plurality of third annular channels isvertically aligned with an associated channel of the plurality of firstannular channels, and wherein the plurality of second channelinterconnects are azimuthally aligned with the plurality of firstchannel interconnects.
 12. The substrate support assembly of claim 10,further comprising: a fourth channel formed within the third plane ofthe electrostatic chuck body, and configured to seat a thermocoupleextended through the support stem coupled with the electrostatic chuckbody.
 13. A substrate support assembly comprising: an electrostaticchuck body defining a substrate support surface; a support stem coupledwith the electrostatic chuck body; an electrode embedded within theelectrostatic chuck body proximate the substrate support surface; aground electrode embedded within the electrostatic chuck body; a firstset of interconnected channels formed within the electrostatic chuckbody between the electrode and the ground electrode; and a second set ofinterconnected channels formed within the electrostatic chuck bodybetween the electrode and the ground electrode.
 14. The substratesupport assembly of claim 13, wherein the second set of interconnectedchannels are radially offset from the first set of interconnectedchannels.
 15. The substrate support assembly of claim 13, wherein thefirst set of interconnected channels are maintained at least 5 mm from aradial edge of the electrostatic chuck body.
 16. The substrate supportassembly of claim 13, wherein the first set of interconnected channelsand the second set of interconnected channels are maintained atatmospheric pressure.
 17. The substrate support assembly of claim 16,wherein an effective capacitance within the electrostatic chuck bodybetween the electrode and the ground electrode is less than or about1,000 pF.
 18. The substrate support assembly of claim 13, wherein theelectrostatic chuck body is characterized by a volume percentage of airgreater than or about 10%.
 19. The substrate support assembly of claim13, further comprising: a heater positioned between the electrode andthe ground electrode, and a third set of interconnected channels formedwithin the electrostatic chuck body between the heater and the groundelectrode.
 20. A substrate support assembly comprising: an electrostaticchuck body defining a substrate support surface; a support stem coupledwith the electrostatic chuck body; an electrode embedded within theelectrostatic chuck body proximate the substrate support surface; aground electrode embedded within the electrostatic chuck body; a heaterembedded within the electrostatic chuck body between the electrode andthe ground electrode; a first set of interconnected channels formedwithin the electrostatic chuck body between the electrode and theheater; a second set of interconnected channels formed within theelectrostatic chuck body between the first set of interconnectedchannels and the heater; and a third set of interconnected channelsformed within the electrostatic chuck body between the heater and theground electrode.